Trigger a 430 Speedlite (film) with 430EX Flash

I have a 4Ti, a 430EZ and a 420EX.  I would love to be able to trig the EZ with the EX type of stuff.  I would use E-TTl for the subjet, and manual for the background with the EZ.  I read somewhere that most optical solutions trying to ignore the preflash are unreliable.  Don't know if it's true.

An idea I have is to use a simple optical receiver with an extension cord on the 430EZ.  I would aim this on the 420EX while it's used as a slave to the 4Ti.  I guess the EX slave don't fire a pre-flash.  This would trig well the 430EZ.

A more certain solution would be a radio trigger like the YN-622. It allows you to install your 430EX on it if you want, and fire the EZ in manual mode.  If you want like me to use the EX off-camera, you will have to buy 3 YN-622.

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Yan